Although many individuals with multiple sclerosis (MS) experience depression, there are no studies on the frequency and effect of peripartum depression among parents with MS.

To examine the frequency of peripartum depression in individuals with MS and its potential association with children’s psychiatric disorders.

We conducted a cohort study in British Columbia, Canada, using linked health databases, of parents with MS and their children, and age-matched unaffected parent–child dyads. The diagnosis of peripartum depression, MS and psychiatric disorders in children was based on information from hospital admission, physician visit and drug prescription claims.

Peripartum depression was significantly more common among MS parents (n = 360) versus unaffected (n = 1207) parents (25.8% vs 18.5%, p value 0.02), especially among MS affected fathers versus unaffected fathers (25.7% vs 10.2%, p value < 0.001). The incidence of psychiatric disorders in children was 3.3 and 2.7 per 100 child-years among children with and without an MS parent, respectively. The rate of psychiatric disorders was significantly higher in children with an MS parent (vs without, hazard ratio (HR): 1.34; 95% confidence interval (CI): 1.03–1.74) and among children with parents who had peripartum depression (HR: 1.87; 95% CI: 1.36–2.55).

Parental MS is associated with a higher risk of peripartum depression and increases the risk of psychiatric disorders in children.